Motive nerve impulses are transmitted as electrical signals along a motorneuron until they reach the neuron ending located on a muscle. The nerve ending contains vesicles filled with acetylcholine, which is the main neurotransmitter in the human body. The nerve impulse stimulates the vesicles to release acetylcholine into the synapse through the pores in the pre-synapse membrane. The acetylcholine diffuses through the synapse gap very quickly (within 1 millisecond) and reaches the post-synapse membrane. The acetylcholine depolarizes the post-synapse membrane, generating an electrical impulse which spreads along the muscle fiber and causes the muscle to contract. This system of neuron-synapse-muscle operates as an "all-or-none" response, that is the stimulus must overcome an excitatory threshold in order for the signal to be transmitted and the muscle to contract. The thresholds of excitation are different for different muscle motor units. A motor unit is defined as the system of one motor nerve, its branches, the synapses located at the end of the branches, and the muscle fibers that are stimulated by the nerve. Both the threshold of excitation and the strength of the incoming nerve impulses can vary to a great degree. An increase in stimulus intensity may bring progressively more units to respond. In fact, improvement in strength, speed and endurance depend mainly on the body's ability to mobilize a greater number of muscle fibers in the contraction. This ability is greatly influenced by temporary factors such as fatigue, stress level and food intake, and by long-term factors such as genetics, general fitness level, conditioning, hormonal levels, age, etc. In the average non-training individual, only about 20-30% of the available muscle fibers become actively involved in the muscle contraction. This percentage is raised in professional athletes to about 40-50% by regular and intensive workouts. Regular workouts, good nutrition and appropriate supplementation lead to an increase in the energy levels of the muscle cell, as well as to an extended growth and branching out of the capillary network, and the optimization of the work of numerous enzyme systems, etc., the result of all this being the lowering of the excitation threshold of the muscle fibers, which facilitates muscle contraction.
The passage of the impulses through the synapse is brief and unidirectional. Once acetylcholine has conveyed the nerve impulses across the synapse, it must be cleared from the gap. The body does this by breaking it down, or hydrolyzing it, to choline and acetyl, using acetylcholinesterase, or simply cholinesterase. Cholinesterase however eliminates some acetylcholine that has not reached the post-synapse membrane, therefore an 100% effective transmission of the nerve impulse through the synapse does not occur. In addition, after continuous or repetitive movement or exercise, fatigue reduces the strength and duration of the impulses generated, and stimulates the release of the inhibitory neurotransmitter gamma aminobutyric acid, which overpolarizes the post-synapse membrane. The amount of acetylcholine released by the pre-synapse membrane also decreases. As a result of these factors, the energy level of the muscle cell is decreased and the excitation threshold becomes more difficult to overcome.
Galanthamine is a known acetylcholinesterase inhibitor. Galanthamine reversibly binds to acetylcholinesterase, inhibiting its action and resulting in an increase in local concentrations of acetylcholine. Galanthamine has been used in the treatment of different diseases of the nervous system such as Alzheimer's disease (U.S. Pat. No. 5,958,903) and Parkinson's disease (U.S. Pat. No. 5,965,571); the treatment of chronic fatigue syndrome (U.S. Pat. No. 5,312,817); as an erectogenic agent in the treatment of male sexual dysfunction (U.S. Pat. No. 5,177,070) as well as the treatment of glaucoma, myasthenia gravis and senile dementia.
Galanthamine is typically used in pharmaceutical compositions in purified form and is obtained by complex chemical extractions from plant sources (U.S. Pat. No. 5,877,172) or chemically synthesized (U.S. Pat. Nos. 5,777,108 and 5,958,903). These processes may be disadvantageous in that they utilize undesirable chemicals such as chlorohydrocarbons and purification processes forming galanthamine salts.
There is great interest in improving the strength, speed and endurance of physical performance, particularly in athletes. One factor which enables athletes to achieve high level performance in sports, particularly in strength and power events, such as weightlifting and body building, is to increase muscular quality, that is to increase the effectiveness of muscle fiber contraction. An inexpensive, non-toxic preparation, preferably in an herbal formulation containing a whole plant extract that enhances the performance of muscle contraction in individuals, thereby improving physical performance, has heretofore not been disclosed.